The prevalence of mental health illness among patients with HIV is a significant public health issue. The translation of discoveries found at the bench to clinical practice (bench to bedside) is critical for advancements in diagnosing and therapeutic intervention to be made. This relationship, however, is not a one-way street, but bi-directional, where observations made in a clinical setting may also stimulate research at the bench. As such, it is important to develop a collaborative, multi-disciplinary community of clinicians and scientists to foster new discoveries with practical application in diagnosing and treating HIV+ persons with neuropsychological illness. To address this need, the Clinical and Behavioral Core will assist basic and clinical investigators wishing to include human subjects from a well-characterized cohort of HIV+ individuals in their studies, including those assessed for neuropsychological function. We will assist new and established investigators in the design and coordination of their studies, the preparation of required forms and approvals and data collection. To achieve this, the Clinical and Behavioral Core will have three primary functions: 1.) Provide the clinical cohort from the Temple Comprehensive HIV program with its infrastructure, operations management and regulatory oversight for clinical studies involving other CNACC cores or non-CNACC clinical collaborators, 2.) Systematically collect baseline and longitudinal neurocognitive, neurologic and psychiatric assessments on patients in Temple's HIV practice in collaboration with the Department of Psychiatry (for our revised application, we have included an expert neuropsychologist with HIV/AIDS neurocognitive testing and analysis experience, recently hired by Temple University Hospital (Dr. Nancy Minniti) and a consultant with internationally recognized expertise in neurocognitive testing, Dr. Kevin Robertson from the University of North Carolina.), and 3.) Develop and maintain a neurodatabase that will contain data from assessments in function #2, as well as relevant immunologic and virologic data from the Temple HIV clinical database and other studies conducted through CNACC.